This invention relates generally to an improved egg white. In another respect it relates to a process which improves the functionality of desugared egg white.
The substance with which this invention is concerned is albumen, the material which is present in greater quantity than either the yolk or shell of the avian egg. As used herein, "albumen" refers to what is popularly known as the "egg white", and is distinguished from "albumin", which is used to refer to a broader class of proteinaceous materials. Egg white is comprised chiefly of protein substances, and the substances generally said to be present are ovalbumin, constituting about 75% of the total solids in the egg white, ovomucoid, ovomucin, ovoconalbumin, and ovaglobulin. The functional characteristics of egg white are determined to a very great extent by the proteinaceous materials in the egg white, and especially by the ovalbumen present. Much of this functionality of egg white is lost in the processing thereof, particularly in drying processes.
The present invention is concerned with desugared egg white. The term "desugared egg white", as used herein, refers to egg white having a glucose content not in excess of about 1%. Preferably, the glucose content will be 0.3% or less. Either of two methods, enzymatic or microbial, can be utilized to prepare desugared egg white. Both methods are well known in the art and are equivalent as far as the present invention is concerned.
The largest use of eggs is in the culinary art. Ingredients such as flour, sugar, fat, and leavening are added to prepare meringues, cakes, custards, and so on. Another extensive use for eggs is in the preparation of other edible materials. Another use for eggs is in the preparation of adhesives.
In many instances, it is desirable to separate the albumen of the egg from the yolk so that advantage may be taken of the peculiar properties of each of these two constituents. An example of the use of the egg white component is in the preparation of angel food cake. In the preparation of angel food cake, the egg white from a large number of eggs is vigorously beaten in the absence of lipid substances to obtain a stable foam, and then the other ingredients are added. Egg white also is very important in the preparation of the so-called "white cake" which relies upon egg white and requires no egg yolk such as is used in, for example, "yellow cake".
Some cake mixes of the foam batter type comprise at least two packages, one of which contains a whippable material such as dried whole egg or egg white, sugar, and additives such as cream of tartar and sodium hexametaphosphate. A second package may contain flour and/or starch, additional sugar, dried egg yolk, a vegetable oil and additives such as cream of tartar and flavoring. To prepare a cake from such a mix, water is added to the ingredients of the first package containing the whippable material, said material is whipped to a stable foam and the ingredients of the second package are gently folded into the foam. The batter thus prepared is then ready for baking. Examples of such twin-packet formulation for angel food cakes are found in U.S. Pat. No. 3,078,168, Bedenk, Feb. 19, 1963.
Cake mixes of the foam batter type comprising an intimate mixture of all the ingredients contained in one package and requiring only the addition of water, beating and baking to prepare a cake have been developed.
The principal problem in using dried egg white in the culinary arts is in obtaining performance from the dried egg white approaching the performance of an equivalent amount of fresh eggs. The eggs, whether whole egg or egg white, are frequently denatured in the course of drying. Further damage can occur on storage and handling. Moreover, dried eggs are probably less effective than fresh eggs when used in combination with certain kinds of flour. For example, they may provide a good foam but when flour is added and the batter baked a loss in egg white functionality is observed.
It has been a common experience to find that certain unaged cake mixes provide extremely good quality, large volume cakes when prepared under carefully controlled conditions but are far less successful when aged. The tolerance to recipe variation of presently available mixes of the foam batter type containing prior art egg white tends to be quite limited.
Another important problem in angel food cakes is cupping (surface depressions) on the inverted side of baked angel food cakes. Thus, the underside of a cake removed from an angel food tin or pan may be observed to have a series of cup-like depressions over a portion of the surface of the cake. Reduced functionality of the egg white appears to adversely affect the surface of the cakes. It also affects color, texture and flavor.
An object of this invention is to enhance the functionality of dried desugared egg white. Other objects of this invention include the provisions of a composition of matter for use in preparing angel food-type cakes which results in cakes with reduced cupping, whiter color, increased volume, excellent texture, and increased recipe tolerance, particularly when dried eggs are employed in a dry cake mix. Other objects will be apparent from the discussion hereinafter of the invention.